Ex vivo method for producing a preparation containing CD4+ T cells specific for EBV structural antigens
The present invention discloses an ex vivo method for producing a preparation containing CD4+ T cells specific for EBV structural antigens for use in the prophylaxis and treatment of patients with a reduced T cell activity in order to prevent or treat growth of EBV infected B cells.
1. An ex vivo method for producing a preparation containing CD4+ T cells specific for EBV structural antigens, the method comprising
incubating B cells with preparations of Epstein-Barr virus-like particles (EB-VLPs) containing EBV structural antigens and devoid of transforming EBV DNA for a time period sufficient to generate a preparation containing B cells presenting EBV structural antigens, wherein said B cells are primary B cells;
admixing said B cells presenting EBV structural antigens with a preparation containing T cells including CD4+ T cells;
incubating said admixture to obtain a preparation including CD4+ T cells specific for EBV structural antigens; optionally
isolating and expanding said CD4+ T cells specific for EBV structural antigens to obtain a population of CD4+ T cells specific for EBV structural antigens.
2. The method according to claim 1 , wherein said B cells are primary B cells contained in or isolated from a peripheral blood mononucleated cells (PBMCs) containing preparation.
3. The method according to claim 1 or claim 2 , wherein said preparation containing T cells including CD4+ T cells is contacted with said preparation containing B cells presenting EBV structural antigens at least two times, preferably 4 to 8 times.
4. The method according to claim 3 , wherein said primary B cells are obtained from peripheral blood or bone marrow.
5. The method according to claim 3 , wherein said primary B cells are obtained from an autologous donor.
6. The method according to claim 3 , wherein said T cells containing preparation including CD4+ T cells is obtained from an autologous donor from whom the B cells are obtained.
7. The method according to claim 2 , wherein said peripheral blood mononucleated cells are additionally treated with immunodominant CD8+ T cell epitopes of the immediate early and early lytic cycle proteins or EBNA3 proteins to generate EBV specific CD8+ T cells together with CD4+ T cells.
8. The method according to claim 1 , wherein the Epstein-Barr virus-like particles (EB-VLPs) are devoid of EBV DNA.